Association Between Traumatic Brain Injury and Risk of Suicide.

Importance: Traumatic brain injuries (TBIs) can have serious long-term consequences, including psychiatric disorders. However, few studies have assessed the association between TBI and risk of suicide. Objective: To examine the association between TBI and subsequent suicide. Design, Setting, and Participants: Retrospective cohort study using nationwide registers covering 7 418 391 individuals (≥10 years) living in Denmark (1980-2014) with 164 265 624 person-years' follow-up; 567 823 (7.6%) had a medical contact for TBI. Data were analyzed using Poisson regression adjusted for relevant covariates, including fractures not involving the skull, psychiatric diagnoses, and deliberate self-harm. Exposure: Medical contacts for TBI recorded in the National Patient Register (1977-2014) as mild TBI (concussion), skull fracture without documented TBI, and severe TBI (head injuries with evidence of structural brain injury). Main Outcomes and Measures: Suicide recorded in the Danish Cause of Death register until December 31, 2014. Results: Of 34 529 individuals who died by suicide (mean age, 52 years [SD, 18 years]; 32.7% women; absolute rate 21 per 100 000 person-years [95% CI, 20.8-21.2]), 3536 (10.2%) had medical contact: 2701 with mild TBI, 174 with skull fracture without documented TBI, and 661 with severe TBI. The absolute suicide rate was 41 per 100 000 person-years (95% CI, 39.2-41.9) among those with TBI vs 20 per 100 000 person-years (95% CI, 19.7-20.1) among those with no diagnosis of TBI. The adjusted incidence rate ratio (IRR) was 1.90 (95% CI, 1.83-1.97). Compared with those without TBI, severe TBI (absolute rate, 50.8 per 100 000 person-years; 95% CI, 46.9-54.6) was associated with an IRR of 2.38 (95% CI, 2.20-2.58), whereas mild TBI (absolute rate, 38.6 per 100 000 person-years; 95% CI, 37.1-40.0), and skull fracture without documented TBI (absolute rate, 42.4 per 100 000 person-years; 95% CI, 36.1-48.7) had an IRR of 1.81 (95% CI, 1.74-1.88) and an IRR of 2.01 (95% CI, 1.73-2.34), respectively. Suicide risk was associated with number of medical contacts for TBI compared with those with no TBI contacts: 1 TBI contact, absolute rate, 34.3 per 100 000 person-years (95% CI, 33.0-35.7; IRR, 1.75; 95% CI, 1.68-1.83); 2 TBI contacts, absolute rate, 59.8 per 100 000 person-years (95% CI, 55.1-64.6; IRR, 2.31; 95% CI, 2.13-2.51); and 3 or more TBI contacts, absolute rate, 90.6 per 100 000 person-years (95% CI, 82.3-98.9; IRR, 2.59; 95% CI, 2.35-2.85; all P < .001 for the IRR's). Compared with the general population, temporal proximity since the last medical contact for TBI was associated with risk of suicide (P<.001), with an IRR of 3.67 (95% CI, 3.33-4.04) within the first 6 months and an incidence IRR of 1.76 (95% CI, 1.67-1.86) after 7 years. Conclusions and Relevance: In this nationwide registry-based retrospective cohort study individuals with medical contact for TBI, compared with the general population without TBI, had increased suicide risk.

Association of Streptococcal Throat Infection With Mental Disorders: Testing Key Aspects of the PANDAS Hypothesis in a Nationwide Study.

Importance: Streptococcal infection has been linked with the development of obsessive-compulsive disorder (OCD) and tic disorders, a concept termed pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS). However, previous studies of this association have been small, and the results have been conflicting. Objective: To investigate the risk of mental disorders, specifically OCD and tic disorders, after a streptococcal throat infection. Design, Setting, and Participants: A population-based cohort study was conducted using data from the nationwide Danish registers from January 1, 1996, to December 31, 2013, with up to 17 years of follow-up. The Danish National Health Service Register provided information on individuals with the registration of a streptococcal test. Data analysis was conducted from January 1, 2016, to February 28, 2017. Main Outcomes and Measures: Individuals were followed up in the nationwide Psychiatric Central Register for a diagnosis of any mental disorder, OCD, or tic disorders. Incidence rate ratios (IRRs) were calculated by Poisson regression analysis. Results: Of the 1 067 743 children (<18 years of age) included in the study (519 821 girls and 547 922 boys), 638 265 received a streptococcal test, 349 982 of whom had positive test results at least once. Individuals with a positive streptococcal test result had an increased risk of any mental disorder (n = 15 408; IRR, 1.18; 95% CI, 1.15-1.21; P < .001), particularly of OCD (n = 556; IRR, 1.51; 95% CI, 1.28-1.77; P < .001) and tic disorders (n = 993; IRR, 1.35; 95% CI, 1.21-1.50; P < .001), compared with individuals without a streptococcal test. Furthermore, the risk of any mental disorder and OCD was more elevated after a streptococcal throat infection than after a nonstreptococcal infection. Nonetheless, individuals with a nonstreptococcal throat infection also had an increased risk of any mental disorder (n = 11 315; IRR, 1.08; 95% CI, 1.06-1.11; P < .001), OCD (n = 316; IRR, 1.28; 95% CI, 1.07-1.53; P = .006), and tic disorders (n = 662; IRR, 1.25; 95% CI, 1.12-1.41; P < .001). Conclusions and Relevance: This large-scale study investigating key aspects of the PANDAS hypothesis found that individuals with a streptococcal throat infection had elevated risks of mental disorders, particularly OCD and tic disorders. However, nonstreptococcal throat infection was also associated with increased risks, although less than streptococcal infections for OCD and any mental disorder, which could also support important elements of the diagnostic concept of pediatric acute-onset neuropsychiatric syndrome.

Head injury as risk factor for psychiatric disorders: a nationwide register-based follow-up study of 113,906 persons with head injury.

OBJECTIVE: Studies investigating the relationship between head injury and subsequent psychiatric disorders often suffer from methodological weaknesses and show conflicting results. The authors investigated the incidence of severe psychiatric disorders following hospital contact for head injury. METHOD: The authors used linkable Danish nationwide population-based registers to investigate the incidence of schizophrenia spectrum disorders, unipolar depression, bipolar disorder, and organic mental disorders in 113,906 persons who had suffered head injuries. Data were analyzed by survival analysis and adjusted for gender, age, calendar year, presence of a psychiatric family history, epilepsy, infections, autoimmune diseases, and fractures not involving the skull or spine. RESULTS: Head injury was associated with a higher risk of schizophrenia (incidence rate ratio [IRR]=1.65, 95% CI=1.55-1.75), depression (IRR=1.59 95% CI=1.53-1.65), bipolar disorder (IRR=1.28, 95% CI=1.10-1.48), and organic mental disorders (IRR=4.39, 95% CI=3.86-4.99). This effect was larger than that of fractures not involving the skull or spine for schizophrenia, depression, and organic mental disorders, which suggests that the results were not merely due to accident proneness. Head injury between ages 11 and 15 years was the strongest predictor for subsequent development of schizophrenia, depression, and bipolar disorder. The added risk of mental illness following head injury did not differ between individuals with and without a psychiatric family history. CONCLUSIONS: This is the largest study to date investigating head injury and subsequent mental illness. The authors demonstrated an increase in risk for all psychiatric outcomes after head injury. The effect did not seem to be solely due to accident proneness, and the added risk was not more pronounced in persons with a psychiatric family history.

Psychiatric treatment following participation in the CapOpus randomized trial for patients with comorbid cannabis use disorder and psychosis.

BACKGROUND: Randomized trials targeting cannabis use disorders in patients with psychosis have generally been unsuccessful. One of the largest such trials was the CapOpus trial, which had an impact on the number of monthly joints used, but not on the number of days with cannabis use or positive or negative symptoms. OBJECTIVE: To investigate the effects of CapOpus on psychiatric treatment. METHODS: Six-month randomized trial on participants meeting ICD-10 criteria for cannabis use disorder and schizophrenia-spectrum psychosis. Participants were randomized to treatment as usual (TAU, n=51) alone versus TAU plus CapOpus (n=52) consisting of motivational interviewing and cognitive behavior therapy. Data regarding psychiatric treatment was obtained from complete nationwide registers. Analyses were intention-to-treat. Cox and poisson regression were used as appropriate. RESULTS: Compared with treatment as usual, participants in the CapOpus group had an overall higher risk of having a psychiatric emergency room contact (hazard ratio 2.02, 95% confidence interval 1.22-3.34). Participants in CapOpus also had more contacts with psychiatric emergency rooms (incidence rate ratio 3.47 (2.64-4.57)) and more admissions to psychiatric hospitals (incidence rate ratio 2.24 (1.65-3.03)); conversely, CapOpus-participants spent fewer days admitted to psychiatric hospitals than treatment-as-usual participants (incidence rate ratio 0.72 (0.68-0.75)). CONCLUSIONS: CapOpus led to earlier and more psychiatric emergency room contacts and admissions that, however, were of fewer days. This pattern could indicate that participants receiving treatment as usual were inadequately treated. However, it cannot be excluded that the differences might be an adverse reaction to the psychosocial intervention.